Tweet
I’m trying to figure out a fuel issue on a 2002 Air Nautique with the small block Chev. I have spark. The fuel pump does not run unless I jumper the relay, the relay is good. I have checked for water in the fuel control cell. I have used a jumper to bypass the kill switch. ANY IDEAS?
-
-
Neutral safety switch or TPS? Hard to say or really even guess...limited info in above post. No crank but you have power....does it crank but not start (assume yes since you said you have spark which should mean the dizzy/cap/wires/plugs are ok?).....sounds like maybe its not getting fuel, you sure its providing enough even tho you hear the fuel pump running, maybe check the pressure on it.
Could you have a ground issue due to corrosion or bad connection, I know that can cause all kinds of issues. Wild guessing -
The motor cranks great and has a strong spark. The only way to make the fuel pump run is to “hot wire” it by bypassing the relay. There 3/4 tank of fuel. It’s like the entire electrical part of the throttle-body fuel system is not powering up. Good battery voltage, no blown fuses, and fuel pump relay is good, just not being activated. Circuit breaker at the back of the motor is working properly. I haven’t been able to find anyone that can test the ECU. Any other ideas??????????Comment
-
From looking through your manual, it looks like you have a fuel pump fuse, which could be your problem. It looks like there's a fuse holder in the engine bay (probably looks like a capped electrical connector) that has fuses for the ECM, fuel pump, and injectors. It looks like the fuse holder is near the ECM, and this would be separate from the breakers.
Beyond that, you need to chase power, and see if it's the power feed to the relay that you don't have 12V on, or if it's the run signal to the relay that doesn't have power (or ground).Comment
-
All the fuses are good and have power. ECM/Batt is powered all the time. The ECM/IND and FUEL PUMP are powered with key on. I'm trying to trace wires. Does anyone know how to locate a good engine control wiring diagram like the ones for the GT 40 engine? Nothing on this site for the smallblock Chev engine control wiring. Called the closest dealer about testing the ECU, was told they just replace them to see if that fixes the issue. Surely there is a better way??Comment
-
I'm guessing the manual linked below should be what you're looking for. Go to the link and there's a 'click here' which downloads it for free. For crank/no-start, go to section 5-22, and there's a whole rundown on troubleshooting it (including MAP and TPS sensors). Good luck.Comment
-
Hi Tom_H, That link you sent is perfect! I hope to get back to that project and track down the issue. Do you know the best place to purchase a new ECM if needed?Comment
Comment